No i'm not, nothing is sure about how he'll fair at HW... But based on how well i've seen him take shots at LHW and his apparent willingness to move up, i'd take a calculated guess that he's not gonna become some chinny dude out of nowhere..
End of the day anyone can get KO'd at HW, it's a risk i'm sure he knows about more than 99% of Sherdog... Evidence suggests Jon has close to Tony Ferguson levels of pain thresh hold.
The fact that he's putting so much time and focus into preparing his body for the move up is a hell of a lot more preparation for a move up in weight than most i've ever seen.
I expect Jones to be around 240-250 on FightNight with not much to back why.